| 摘要 |
A drive mechanism for a drug delivery device which can be switched between a normal operation mode and a reset mode comprises; a housing (17, 13) having a proximal end (8) and a distal end (7), a piston rod (12) which is adapted to be displaced in a distal direction with respect to the housing (17, 13) for delivering a dose in a normal operation mode of the drive mechanism, and which is adapted to be displaced in the proximal direction with respect to the housing (17, 13) in a reset mode of the drive mechanism, and a drive member (20) which is rotationally moveable in a rotation direction with respect to the housing (17, 13), wherein, in the normal operation mode, the drive member (20) is coupled with the piston rod (12) so that rotational movement of the drive member (20) in the rotation direction with respect to the housing (17, 13) is converted into movement of the piston rod (12) in the distal direction with respect to the housing (17, 13), and wherein, in the reset mode, the piston rod (12) is decoupled from the drive member (20). |
